The DFRobot URM13 is a compact ultrasonic ranging sensor with an open single-probe design. It supports three communication methods — TRIG pulse (SR04-compatible), UART, and I2C — making it versatile for a wide range of applications. The sensor operates on 3.3 V or 5 V, compatible with Arduino, Raspberry Pi, and other common development boards.

An integrated precision circuit and smart detection algorithms enable automatic ambient and electrical noise detection, with real-time calibration of sensor parameters for stable performance in demanding environments. In UART mode, the sensor uses the standard Modbus-RTU protocol with receive/send control output, allowing easy expansion to RS485 via an external transceiver.

Key Features

• Triple Interface – TRIG pulse (SR04-compatible), UART (Modbus-RTU), and I2C
• Wide Measuring Range – 15 cm to 900 cm with 1 cm resolution
• Automatic Noise Calibration – Real-time detection and adjustment for ambient and electrical noise
• RS485 Ready – UART mode with Modbus-RTU and TX/RX control output for RS485 expansion
• Compact Design – Small, lightweight single-probe form factor
• Wide Voltage Range – 3.3–5.5 V DC

Specifications

• Power Supply – 3.3–5.5 V DC
• Max Current – 350 mA (instantaneous)
• Measuring Range – 15–900 cm
• Resolution – 1 cm
• Accuracy – 1%
• Measuring Frequency – Up to 10 Hz
• Operating Temperature – −10 °C to +70 °C
• Dimensions – 22 × 20 mm

Ideal For

• Robotics obstacle detection and navigation
• Distance measurement and level sensing
• Industrial monitoring with RS485 networks
• Arduino and Raspberry Pi projects

Package Contents

• 1× URM13 Ultrasonic Sensor

Resources

• Product Wiki (DFRobot)